Apparatus for producing foam



P 1931. H. BURMEISTER APPARATUS FOR PRODUCING FOAM Filed Nov. 12, 1927INVENTOR HANS BURME/STER BY MM- ATTORNEY Patented Sept; 15, 1931 UNITEDSTATES PATENT OFFICE HANS BURMEISTER, OF BERLIN, GERMANY, AS SIGNOB TOPYRENE-MINIMAX CORPO- RATION, A CORPORATION OF DELAWARE Arrana'rus r03.raonucme rom Application filed November 12, 1927, Serial No. 282,786,and in Germany March 31, 1927 The present invention relates to apparatusfor producing foam for fire extinguishing purposes and has for an objectto rovide improved means for combining pow er and water to form foam.

The nature and objects of the invention will be better understood from adescription of a particular embodiment of the invention, for the purposeof which description reference should be had to the accompan ing drawingforming a part hereof an in which- The figure is a central sectionalview of an illustrative apparatus embodying the principles of theinvention.

The apparatus shown com rises a hopper 5 for foam forming powder, w ichhopper terminates at its bottom in a plurality of restricted outlets 6.Opposite each restricted outlet is a nozzle 7 positioned to cooperatewith the outlet to form an ejector. In order to feed the foam formingpowder to the ejectors, a suitable spray arrangement 8 is provided abovethe ejectors so arranged as to wash the desired quantity of powder intothe ejectors. As shown, t e spray device is formed with a slot 10extending, preferably, entirely around the same to project a. sheet ofwater outwardly and downwardly, as 1nd1- cated by the arrows. Thenozzles of the spray device are convenientl formed as one integralstructure and prefera ly are supplied by one water inlet, in order thatthe pressure and therefore, the quantity of water discharged from bothmay be maintained in desired ratio.

By this arrangement as the water pressure P increases, thus increasingthe quantity of water fed to each outlet by its corresponding nozzle,the quantity of water dischar ed by the spray increases simultaneously,t ereby to feed a larger quantity of powder.

. In the arrangement shown, the nozzle member 11 is formed as acontinuous part of the water inlet conduit 12, and may have, for

example, four nozzles 7. In the upper end of the nozzle member, a spider13 is secured to provide suitable support for the bolt 14 adj ustablycarrying the cone 15, which constitutes the upper member of the spraynozzle above described. A look nut 16 holds the bolt 14 in adjustedposition.

Each outlet 6 is preferably tapered and so shaped as to form with thecorresponding nozzle 7 an effective ejector.

The foregoing description of a articular embodiment of the invention isilustrative merely and is not intended as defining the limits of theinvention.

I claim:

1. In apparatus for producing fire extinguishing foam a hopper for foamforming powder, a water discharge member extending into the hopperthrough the bottom thereof, a nozzle connected with said member andadapted to discharge a jet of water outwardly through an opening at thebottom of said hopper, and a spray device connected with said memberadapted to discharge water into the powder in said hopper and wash thesame into the path of said ]et.

2. In apparatus for producing fire extinguishing foam a hopper for foamforming powder, a water discharge member extendin into thehopper throughthe bottom thereo a nozzle connected with said member and adapted todischarge a jet of water'outwardly through an opening at the botom ofsaid hopper, and a device connected with said member adapted todischarge an annular spray of water into the powder in said hopper andwash the same into the path of said 3e 3. In apparatus for producingfire extinguishing foam a hopper for foam forming owder, a waterdischarge member extendmg into the hopper through the bottom thereof,said member having a plurality of outlets adapted to discharge waterthrough openings at the bottom of said hopper, and a device connectedwith said member adapted to dischar e a sheet of water into the powderin said hopper and wash the same toward said 0 nin gs HANS BURMEISTER.

